Powdered coke product



Dec. 9, 1930.

v v. RUNGE PC )WDERED COKE PRODUCT Filed June 12, 192s 2 Sheets-sheet 1Zigi.

Dec. 9, 193.0. w. RUNG I 1,783,983

PQWDERED COKE PRODUCT Filed June 12, 1925 2 Sheets-Sheet 2 Patented`Dec. 9, 1930 UNITED STATES PATENT oF-FlcE WALTER RUNGE, or EAST ORANGE,NEW JERSEY, AssIeuv'oR, EY MESNE ASSIGN- MENTS, TO INTERNATIONAL COALDELAWARE l CARBONIZA'IION COMPANY, A CORPORATION OF POWDERED COKEPRODUCT Application led J'ne 12, 1925i. Serial No. 36,598.

The invention relates to the processing of coal for production ofsmokeless fuel thereby. It is particularly directed to a productobtained bythe pulverizing and partial carr bonizing of the coal underconditions to produce a product in relatively finely divided state andunder conditions to eliminate a substantial portion-notall-of thehydrocarbon volatile content of the coal and so that many of theparticles will each be in the form of relatively small hollow spheroidswith one or more windows-visible under the microscope-in vthe surfacethereof. The processing of the coal 1n the manner herein .15 describedslightlywincreases the area and volume'of the individual particles.

The product which is the basis of this invention is particularly adaptedfor burning asfuel. A f" As illustrative ofthe manner in which theinvention may be realized, reference. is made to the accompanyingdrawings constituting a part of this specification. It will be manifestfrom what follows that the invention is not limited to the precisemethods or apparatus specifically described but may be realized invarious manners and ways without departing l 4ment in a gaseous mediumat approximately 650 degrees F. This reproduction ofv the`micro-photo-graph `was made under a mag` nifcation of 155Adiameters.AI-I'ere it -will'be noted that the edges ofthe fragment have becomerounded due presumbaly to fusion `and the. fragment is solid and opaque.The .gen. eral shape is spherical. This is illustrative of theappearance of the minute fragments of coal after a hot gas pretreatmentat the approximatetemperature just specified.

Figure 4 is a reproduction of a microphoto-graph illustrative of arelatively hollow `spheroid having a shell-like structure p with Windowsin the shell-like structure. This is a particle of the finished productafter the` low temperature carbonization of ti complete process, duringwhich carbonizatio'n the .average temperatures approximated 1000 degreesF. This figure is a reproduction of a microfphoto-grap'h taken under amagnification of 155 diameters.

The figures above referred to are suiicient to illustrate fundamentalfeatures described in connection with this. invention. Howeverthere hasbeen incorporated in the patent file 'as originally presented in theUnited States Patent Oilice, a set of micro-photographs duly labeled andwhich illustrate in refined details actual structures realized fromperforming the invention prior to lino the amy ication for patent in theUnited` tates l I.

Patent O ice. l

Referring now to the drawings in detail l l .1 indicatesapulverizing-mill wherein the coal to be processed is initiallypulverized to the desired de ee of fineness for example to -afineness....suc thatapproximately 60% will pass through a 200` -meshscreen (a screen defined by wires crossing at right angles to eachotherso as to'form forty thousand openings per square inch) and so thatsubstantially all of the .pulverized coal will fpass through a 40 meshScreen..

The pulverized coal is pneumatically conve ed to acyclone'separator 2where it is collected and from which it is conveyed to a receivinghopper 3 from which it is fed eby a suitable means 4 into the top of aprefretort the pulverized coal in cloud-like for- 'mation. movesdwnwardly with" delayed gravitationinto and counter to slowly risin vhotpretreating gases which are introduc in the lower regions of the retortas at. 6. .These pretreating gases are preferably, al-

;.though not necessarily, heated air.- When -air isth'us employed itconstitutes a hot oxi- -treating retort l5. Within this pretreatingwhich itis fed by any suitable means as 9 into the top of a carbonizingretort 10. Herein the pretreated pulverized coal settles in cloud-likeformation and with retarded gravitation into and counter to slowlyrising hot carbonizing gases such -as the gaseous products of com ustionof a portion of the gas removed from the top of the carbonizing retort10 which serve to reduce' the coal into semi-coke. The hot gases foreffecting the carbonization within the carbon-- izing retort 10 aresupplied at the bottom thereof as at 11 and the temperatures of theserising hot gases is such that the coal temperature is approximately 1000degrees F. The settling or gravitatingfof thecoal undergoing thecarbonizingoperation is sufficiently delayed b the upwardly moving hotgases to effect t e desiredl degree of carbonization or in other words,a suiicient length of time to substantially reduce the hydrocarbonvolatile content of the coal and also a sutlicient len h of time toreduce the oxygen content of t e coal below that which the original coalpossessed. It will be manifest that in the plant for realizing theinvention suitable pipings and other instrumentalities should beemployed for withdrawing and disposing ofthe pretreated gases and forcollecting, purifying, storing or otherwise handling of the gasesemployed in or given olf by the carbonization. Y

As to the effect of the different steps upon the Vcoal undergoingtreatment, this is illustrated b Figures 2 to 4 inclusive. All the coalun ergoing treatment is in relative finely divided form being in theform of minute fragments or particles and a typifying illustration of afragment of raw pulverized coal is seen in Figure 2. Here it will benoted that the prominent characteristics are the sharp lines and edges.

When the pulverized coal undergoes the hot Apretreatment to wit underconditions such that the pretreating gases approximate 650 F. it losesthese sharp edges andthey are replaced by relatively smooth roundedsurfaces. Where the pretreating gases are hot oxidizinggases Vsuch4 as amixture of air and gaseous combustionv products of a portion of the gasremoved from the carbonizing retort 10 then the pretreated particles ofpulverized coal take on, as determined by chemical analysis, anothercharacteristic in that theyy have been oxidized bythe hot pretreatingair so that`for exampe, pulverized coal` having an initial oxyg ncontent of 71/2% may after ,the pretreatment, have an oxygen content of81%. has been thus pretreated and after having been `subjected to theabove mentioned low temperature carbonization, for example at coaltemperatures of approximately 1000 degrees F., becomes further changedas to its physical and structural characteristics as is clearlyillustrated in Figure 4.

A study of the product resulting from the low temperature carbonizationof the pretreated. coal shows that it is semi-coke composed mainly ofspheroids, as shown in Figure 4, most of which are relatively hollowandmany .of which have what appears to be and what, for convenience Ihave termed, windows in the surface thereof, which windows are notapparent to the naked eye but with the aid of transmitted light arevisible under the microscope. i

It may not be desirable in all instances to subject the pulverized coalt'o a heat pretreatment prior to the carbonization but with the directlow temperature carbonization, the particles are,` as a general rule,slightlylarger than in the instance where the particles are produced bythe pretreatment which is followed byv thelow temperafThe coal whichture carbonization. This is best discernable by comparative screenanalysis of the raw pulverized coal, the product'realized by the directca-rbonization, and the product derivable by the dual process to withthe pretreating process which is' followed by the low temperaturecarbonization.

-According to the process of this application, one can take coal havinga hydrocarbon volatile content of, for example 34%, and an oxygencontent of approximately 7% to 10% and readily obtain therefrom thedesired resulting semi-coke product. When apretreatment is employed thesteps of a specific aspect of the invention would Ainclude thefollowing: pulverizing the raw coal to a Iineness such thatapproximately 55% to 65% of the coal will pass through a 200 mesh screenand so that substantially all of-the pulverized coal will pass through a40`mesh screen, thereafter pretreating the pulverized coal by suspendingthe coal in the form of dust clouds in a current Yof slowly upwardlymoving hot gases, preferably but not necessarily hot oxidizing gases, attemperatures of approximately 650 F. in the manner described, wherebythe coal is dried, the hydro-carbon volatile content but slightl/'yreduced, the density slightly lessened, the oxygen cont-ent slightlyincreased, the sharp edges of the coal fragments eliminated and theouter surfaces of the coal fragments rounded of. This pretreatment isfollowed by: the separating of the treated particles from the treatinggases and the showering of the pretreated coal in the form of dustclouds into and counter to a current of slowly upwardly moving hotcarbonizing gases at l largely of particles in the form of relativelyhollow spheroids'of` high porosity and low density relative to that ofthe original coal.

Many of the spheroids have a shell-like delining structure with windowsin the surface thereof. The spheroids are of such size that 5% to 20% ofthe semi-cokewill pass through a 200'mesh screen and such thatpractically all will pass a 10 mesh screen. The semicoke thus producedis in fact a low temperature coke and may have a hydrocarbon volatilecontent of approximately 8% to 12%.

I believe that I am the iirst to product defined in the claims. What isclaimed is:

1. A powdered coke product obtained by pulverizing coal to convert itinto finely divided form, by subjecting the pulverized coal tothe'preheating action of hot gases having temperatures of approximately650 degrees F. whereby the surface of the coal particles are roundedoff, the volatile content slightly reduced andthe densityslightlylessened, and by subjecting coal thus preheated and after it hasbeen separated from its pretreating gases to low temperaturecarbonization` in suspension in a gaseous carbonizing medium to producea semi-coke having a hydrocarbon volatile content of approximately 8% to12% and in which most of the particles have been converted intosubstantially hollow spheroids with shell-like defining structures, thesize of which spheroids is such that practically all will pass through a10 mesh screen. 2. semi-coke according to claim 1 consisting oi?spheroids of such form and vsize that approximately 5% to 20%. will passthrough a'200 mesh screen.

3. powdered coke product obtained by the method comprising subjectingpulverized coal to a preheating in a gaseous medium.

wherein the temperature of the coal is approximately 650 degrees F.whereby the surfaces of the coal particles are rounded olf, thehydrocarbon volatile content slightly reduced and the density lessened,separating the preheated coal from the said gaseous medium andsubjecting the separated preheated coal to carbonization by showering itinthe form of a dust cloud into an upwardly moving current of hotcarbonizing gases with the temperature of the coal at approximately 1000degrees F., and separatingv the solid carbonized material from thecarbonizing gases, the said product beingcharacterized by an 8% to 12%hydrocarbon volatile con-4 tent and the particles of which are mainly inthe form of relativelyT hollow spheroids with a shell like definingstructure the size produce the- .v volatile content than the originalcoal, the

of which is such that substantially all of them will plss through a 10mesh screen.

'4. the method comprising subjecting pulverized coal to preheating in ahot oxidizing atmosphere wherein the temperature of the coal isapproximately` 650 degrees F. whereby the oxygen content of the coalisslightlyv increased, separating the oxidized products from theoxidizing atmosphere and subjecting them to carbonization by showeringthemI in the form of a dust cloud intov a slowlyupwardly moving currentofhot carbonizing gases with the ltemperature of the coal atapproximately 1000 degrees F. and separating and collecting thecarbonized residue whereby there isproduced a residual product havinslightly less oxygen thanthe original coa and having substantially lesshydrocarbon said residual product consisting largely of powdered cokeproduct obtained by I particles in the form of relatively hollowspheroids with a shell like refining structure `and of a size such thatpractically all of the spheroids will pass a 10 mesh screen.

5. A powdered coke product obtained by .the method comprising subjectingpulverized l coal of a ineness such that approximatel 55% to 65% willpass throu h a' 200 mesh, screen and so that substantial y all of itwill pass through a 40 mesh screen, to preheating so thatthe temperatureof the coal is approximately 650 degrees F. and subjecting the preheatedcoal to carbonization by showering it in the form of a dust cloud intoan upwardly moving current of hot carbonizing gases withthe'tempei'ature of the coalat approximately 1000 degrees F. and

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separating the solid lcarbonized residue from the carbonizing gases, thesaid product consisting largely ofparticles in the form of relativelyhollow spheroids withv a. shell-like defning'structure and being of suchineness that approximately 5% to 20% will pass 'through a 200 meshscreen and so that substantially all will pass through a 10 mesh screen.

6. -A powdered ,coke product obtained by the method comprising showeringpulverized coal in the form of a dust cloud into an upwardly movingcurrent of hot oxidizing gases with the temperature of the coal at aproximately 6.50 degrees whereby the su aces of the coal particles arerounded olf and the oxygen content slightly increased, separating theoxidized products from the oxidizing atmosphere and subjecting them tocarbonization by showering them in the form of a dust cloud into aslowly upwardly moving current of hot carbonizing gases with thetemperature of the coal at approximately 1000 degrees F. and separatingand collect- `ing the carbonized residue whereby there is produced aresidual product having slightly less oxygen than the original coal andhaving substantially lessv hydrocarbon volatile'cohtent than'theoriginal eoal, the said residual product consisting largely of articlesin the form of relatively hollow sp eroids with a 5 shell like definingstructure and of a size such that practically all of the spheroids willpass a l0 mesh screen.

In testimony signed my name.

whereof I have hereunto WALT/ER RUNGE.

